Question

Monochromatic light passes through two narrow slits and forms an interference pattern on a screen.
(a) If the wavelength of light used increases, will the distance between the maxima (1) increase, (2) remain the same, or (3) decrease? Explain.
(b) If the slit separation is 0.25 mm, the screen is 1.5 m away from the slits, and light of wave-length 550 nm is used, what is the distance from the center of the central maximum to the center of the third-order maximum?
(c) What if the wavelength is 680 nm?